Water Well Journal
Issue link: http://read.dmtmag.com/i/705618
If piping, pumps, tanks, and tools are used for drilling, pump work, develop- ment, or cleaning—they should be cleaned, rinsed, and disinfected. Aside from the yard, it is difficult to keep drill rigs and equipment clean. Some problems can be avoided by hav- ing a clean area at the job site where all bits and drill pipe, surge blocks, and other downhole tools are placed instead of being placed on the ground, to avoid concerns of potential influence. It is generally advised that a simple, handheld garden type sprayer be mixed and placed on site with a disinfection solution. All equipment going into the well can be sprayed down prior to being introduced, again reducing the potential for influence. Generally, a potable water and sodium hypochlorite solution is suffi- cient to kill the offending organisms, once bulk debris has been removed. In discussing cleaning efforts with various contractors, there are several commer- cially available products that are com- monly used. These include Alconox, Liquinox, and Detergent 8, all of which are detergents designed to clean a vari- ety of environmental contaminants. For work on environmental sites or industrial sites with a greater potential for surface contaminants present, con- tract requirements may stipulate the rig and equipment be steam cleaned before being allowed on site. I also found in my discussions with drillers and installers the use and mixing rates for each of these methods varied greatly. More often than not, the attitude was a little is good, so how about some more? A more colorful way to describe the rates of some—"glug, glug out of the jug, that should do the trick." Per the manufacturer's website and guidelines: Alconox is a powdered, an- ionic (negative charge) detergent, it is mixed with water at a ratio of 1:100. Liquinox is a liquid, anionic detergent, which is blended with water at a rate of 1:100. Detergent 8 is a low-foaming, phosphate-free detergent used for re- moval of oils and other more dynamic fouling. Detergent 8 is used at a rate of 3:100, blended with water. Each of these products have an alkaline pH (8.5 to 11) and should be treated with care, as with all chemicals on site. In mixing a chlorine-based solution, we recommend using a new source of sodium hypochlorite (bleach), free of perfumes or surfactants, mixed with potable water. Typically, a 50 ppm solu- tion is sufficient, but 100 ppm is more commonly used. For mixing a 50 ppm solution using a 6% concentration of sodium hypochlorite (store-bought bleach), this accounts for 0.1 oz. (3 mL) of bleach per 1 gallon (3.8 L) of potable water; for a 100 ppm solution, double the amount of bleach (0.2 oz. or 6 mL). We strongly advise against use of any phosphate-based solutions for the cleaning of well equipment, piping, or wells. While these products have been approved by NSF, they are not approved for potable well use due to the material acting as a potential stimulant and nutri- ent source for bacteria. What about well construction materi- als? These materials are just as suscepti- ble to exterior influences while sitting at the job site. Screen, casing, and column pipe should be kept in a secure location, raised up off the ground, with the ends closed (if possible). Filter or gravel pack, a magnet for feral or adventurous domestic cats, should be kept in a sealed super sack if possible, or on a tarp with a tarp cover- ing the pile. Visual inspection of the material is advised before placement downhole. Additionally, use of a sodium PVC casing awaits installation. The materials are kept raised by timbers, wrapped in plastic, and banded to prevent influence or contamination. Clean, safe, and secure: supply rig on site for monitoring well installation. Poly tank is filled with potable water for use during site work. SCHNIEDERS from page 19 20 August 2016 WWJ waterwelljournal.com